As a control method of a plant disease a biological control technology not using a conventional chemical pesticide but using a microorganism isolated from the natural world has drawn attention, and several microbial pesticides have been commercialized. However, existing microbial pesticides have drawbacks that the effect is not stable and a range of applicable diseases is rather limited compared to a chemical pesticide. Due to such a situation, there is a demand for a novel microbial pesticide applicable to a new disease and exhibiting a stable controlling effect.
Examples of plant disease controlling agents using a microorganism, which have been registered and used as a microbial pesticide, include a Talaromyces flavus agent, a Pseudomonas fluorescens agent, a nonpathogenic Erwinia carotovora agent, a Trichoderma atroviride agent, a Bacillus simplex agent, and a Bacillus subtilis agent.
As a nematode controlling agent using a microorganism, a Pasteuria penetrans agent, and a Monacrosporium phymatophagum agent have been registered and used as a microbial pesticide.
A plant disease controlling agent using a bacterium belonging to Bacillus amyloliquefaciens has been disclosed in Japanese Patent No. 2955655 (Patent Literature 1). The active ingredient of the plant disease controlling agent is a product of a microorganism, and the bacterium itself is not utilized as a pesticide. Further, there is no description at all about promotion of plant growth, nor nematode control.
Meanwhile, a plant disease controlling agent using a bacterium belonging to Bacillus amyloliquefaciens has been disclosed in Japanese Patent No. 5198690 (Patent Literature 2), but the bacterium is categorically different from a strain according to the present invention.
Further, a microbial pesticide, which is able to control simultaneously a filamentous fungal disease and a bacterial disease, and in which a living bacterial cell itself is effective, has been disclosed in Japanese Unexamined Patent Application Publication No. 2009-247302 (Patent Literature 3), but there is no description about promotion of plant growth, nor nematode control.
A plant disease controlling agent using a bacterium belonging to the genus Bacillus, which is able to be applied to a wide range of plant diseases and effective to a corn rootworm, has been disclosed in Japanese Patent No. 3471815 (Patent Literature 4, WO98/050422), but there is no description about promotion of plant growth, nor nematode control.
Further, a Bacillus sp. D747 strain, which can be applied to plant disease control and insect pest control, has been disclosed in Japanese Patent No. 4071036 (Patent Literature 5, US2004/265292), but there is no description about promotion of plant growth, nor nematode control.
A nematode controlling agent using a bacterium belonging to the genus Bacillus has been disclosed in Japanese Patent No. 3471811 (Patent Literature 6, WO96/032840). The active ingredient of the nematode controlling agent is a bacterium of a Bacillus firmus strain or a spore thereof having nematicidal activity, but there is no description about promotion of plant growth, nor plant disease control.
A nematode controlling method with a nematicidal toxin produced by a novel Bacillus thuringiensis strain has been disclosed in Japanese Patent No. 4359653 (Patent Literature 7, WO1997/012980), but there is no description about promotion of plant growth, nor plant disease control.
Although in agriculture a chemical fertilizer is an important agricultural material influencing the yield of a crop, 30 to 50% of a chemical fertilizer component applied is diffused into the environment without being utilized by a crop to cause eutrophication of a river, pollution of groundwater or the like. In this connection, since a large amount of a fossil fuel is consumed in producing a chemical fertilizer, costs of a chemical fertilizer have been increasing in step with the escalating fossil fuel prices. Further, nitrogen oxide (NOX), which is a degradation product of a nitrogen fertilizer, is said to have a greenhouse effect approx. 300 times as strong as carbon dioxide, and there is growing concern about global warming therefrom. Meanwhile, future food shortage is anticipated in view of the global population increase, and therefore use of a material for increasing the crop productivity is essential and there is an increasing need for an environmentally more friendly material substituting a conventional chemical fertilizer.
In light of such circumstances, researches for increasing the farm product yield utilizing a soil microorganism have been carried out mainly with respect to broad range of Rhizobium bacteria (root nodule bacteria), Pseudomonas bacteria, and Bacillus bacteria, however only few have been put into practical use due to limited effectiveness.
As described above, there has been a strong demand for a microorganism, which can reduce a load on the environment without relying upon a chemical pesticide and a chemical fertilizer, and control a plant disease and a nematode, as well as promote plant growth.